st/glsl_to_tgsi: don't increase immediate index by 1.

Immediates are stored into a separate table, and are
consolidated, so if we get an immediate we don't need
to offset it as the index it has is correct.

Cc: "11.2 12.0" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

src/mesa/state_tracker/st_glsl_to_tgsi.cpp

@@ -816,7 +816,7 @@ glsl_to_tgsi_visitor::emit_asm(ir_instruction *ir, unsigned op,
 
             if (glsl_base_type_is_64bit(dinst->src[j].type)) {
                dinst->src[j].index = initial_src_idx[j];
-               if (swz > 1) {
+               if (swz > 1 && dinst->src[j].file != PROGRAM_IMMEDIATE) {
                   dinst->src[j].double_reg2 = true;
                   dinst->src[j].index++;
 	       }